Body cameras became popular after police shot dead an unarmed teenager in Ferguson, MO in 2014 but the devices have received mixed reviews from civil rights leaders, who have questioned the body camera program policies of some police departments, and law enforcement leaders, who have complained that their line of sight is easily blocked.

Cameras on guns provide a better point of view than body-worn cameras, since they are usually aimed directly at the suspect and are less likely to be blocked when an officer shields their torso behind something, say proponents of the technology such as Centinel Solutions, one of the first companies to deliver the devices to police departments for testing.